Extended batch language v3.14

        Entry:
          AH = function
              00h to 5Fh chained to previous handler
              60h to 6Dh reserved, return immediately
              80h to FFh chained to previous handler
              6Eh clear ??? counter/flag
              6Fh return counter/flag that AH=6Eh clears
              70h ???
                  AL = ???
              71h ???
                  AL = ???
              72h ???
              73h insert byte at end of keyboard buffer
                  AL = byte to insert
              74h insert byte at front of keyboard buffer
                  AL = byte to insert
              75h ???
              76h get keyboard "stack" status
                  AL = 'K' if kbd read will read physical keyboard
                       'S' if it will read EBL internal keyboard buffer
                  AH = ???
              77h clear internal keyboard buffer
              78h ???
                  AL = ???
              79h ???
              7Ah ???
                  AL = ???
              7Bh ???
                  AL = ???
              7Ch ???
                  AL = ???
              7Dh ???
                  AL = ???
              7Eh clear buffer for ???
              7Fh installation check
        Return:
          CX = version in BCD
          DI = segment of ???
          BX = segment of next program's PSP???

        Notes:  Extended Batch Language is a batch-file enhancer by Seaware
                the chaining does not check whether the interrupt had
                been hooked before, so if you try to chain when the
                previous vector was 0000h:0000h, you'll be in trouble
INT 65          Reserved for user interrupt